In exploration for oil and gas, the use of seismic instruments is well known. Typically, a large number of transducers or geophones are positioned at desired locations on the ground. Geophone cables run from each of the geophones and join a central or main cable which runs to a remote acquisition module which is typically located a distance from the central data acquisition location which is conveniently a vehicle. There may be a large number of remote acquisition modules and geophones. After positioning the geophones, an explosive charge is set off. The signals from the formation of interest are transmitted from the individual geophones to the remote acquisition module and, thence, to the vehicle where the received data is compiled and processed as desired.
The main cable containing the individual geophone cables is connected directly to the remote acquisition module. Typically, the connector on the remote acquisition module is a bayonet type connector with a plurality of male pins extending therefrom. It mates with the female connector on the end of the main cable. There are, however, disadvantages with the present connection system.
There is considerable abuse of the main cable, the geophones and the remote acquisition modules in the field as can be readily understood by noting the field conditions under which such exploration activities may be taking place. The main cable can be twisted or driven over by vehicles. The remote acquisition module can likewise be abused. Similarly, the connector can simply wear out after a certain number of connection and disconnection cycles have occurred. The result of this abuse and aging is a deterioration of the connection between the main cables and the remote acquisition modules which affects the integrity of data transmission between the geophones and the remote acquisition module. To prevent problems in data transmission, the connection must be replaced.
However, to replace the connector between the remote acquisition module and the cable, it is necessary to open the module. The modules are well sealed to prevent damage to the electronics within. By opening the module, the electronic components are exposed and the ambient conditions under which such exposure takes place can cause unnecessary damage to the electronics which, again, affects the integrity of data acquisition. Test equipment to test the integrity of the module after the module has been opened may likewise not be available in the field. Alternatively, the module can be removed from operation and shipped to a remote location where connection replacement can take place under laboratory conditions and where testing equipment is available. Such removal, however, creates downtime and shipping costs. Acquisition modules are expensive and it is not desirable to have such downtime if it can be reasonably avoided.